The regeneration of a catalyst entails contacting the catalyst with a regeneration gas. Typically, the regeneration process includes burning, or combusting, carbon deposits on the catalyst, or coke. The coke is combusted with a hot, but oxygen lean gas to regenerate the catalyst. The catalyst requires a sufficient residence time to flow through the regenerator and to enable sufficient time for combusting the coke on the catalyst.
The catalyst typically flows down through a regenerator as a fluidized bed, with the regeneration gas, or combustion gas, flowing upward through the catalyst bed to remove the coke on the catalyst.
The typical process often develops uneven combustion, and therefore uneven regeneration of the catalyst.